Lumia 930 - Why is the browser viewport size so small?

[JHuybrighs]

I did a test on the Lumia 930, which has a 5" HD display of 1920x1080, and discovered that the IE browser's viewport is 320x525 in portrait mode and only 480x233 in landscape. For portrait this is more or less up to current standards and comparable with other high-end phones like iPhone5, HTC One mini, etc,. Landscape mode however is really poor (and actually worse than the first Samsung Galaxy I9000 phone from 2010, if I remember its launch date well).
I am a web developer and this means that when you put the phone in landscape mode all web content (that is not an image), would fill the screen horizontally with only 480 pixels. That results in larger text then what you would expect for a 5" display which has such a high dpi figure.

Has anybody an idea why Microsoft reduced the viewport in such a way?

 

[manicottiK]

Microsoft changed the way that devices report their width to be account for the physical size of the device. The device should report its actual width (in inches) multiplied by 160 DPI. When the device isn't sure of its own size, it falls back to the default widths of 320 and 480 (portrait and landscape) with the height computed using the aspect ratio of the display.

How are you detecting the width? Since you're getting the default widths, I think that something is wrong.

 

[JHuybrighs]

Thanks for the feedback.

I tested the size simply with jquery's $(window).width() and height() and it returns 480 resp. 233 in landscape mode. The viewport is standard: <meta name="viewport" content="width=device-width, initial-scale=1.0">.
I also clearly see that text is considerably larger in landscape compared with how it renders in portrat mode.